import java.util.concurrent.atomic.AtomicInteger;


public class UniqueID {

	private static UniqueID instance = null;
	
	public static UniqueID getInstance() {
		if(instance == null) {
			instance = new UniqueID();
		}
		return instance;
	}

	private static final AtomicInteger counter = new AtomicInteger();

	public static int nextValue() {
		return counter.getAndIncrement();
	}

}
